This program requires the SBCL Common Lisp system
(http://www.sbcl.org) to compile. Because of its use of a new feature
of SBCL, "(save-lisp-and-die :executable t)", vcs-tree requires SBCL
version 0.9.4 or greater to compile
Once you have SBCL installed on your system, you can give the command
make
which will create the executable file "_vcs-tree". You can then copy
that file to any directory in your path, such as /usr/local/bin/
Additionally, the small shell wrapper "vcs-tree" can be used and copied to
a directory of binaries along with _vcs-tree.